Work-guiding mechanism for sewing machines



Aug. 27,1946. I w MYERS I 2,406,623

WORK-GUIDING MECHANISM FOR SEWING MACHINES Filed Dec. 30, 1943 Z SheetS-Sheet 1 v 3 i 3 lljalzfer yfem Aug. 27, 1946. w, M E S 2,406,623

WOBK-(JIDING MECHANISM FOR SEWING MACHINES Filed Dec. 30, 1945 2 Sheets-Sheet .2

J2 l r an/bum v I ZZJa/ter 972 794 6 azm Patented Aug. 27, 1946 WORK-GUIDING MECHANISM FOR SEWQING MACHINES Walter Myers, Stratford, Conn., assignor to The Singer Manufacturing Company, N. J a corporation of New Jersey Elizabeth,

Application December 30, 1943, Serial No. 516,158

This invention relates to work-guiding mech-. anisms employed in connection with sewing machines for spiral stitching purposes, such as spirally stitching the brims of sailors hats.

The invention has for an object to provide a work-shifting mechanism assembly unit with which sewing machine units may be conveniently or interchangeably associated.

Another object of this invention is to provide means facilitating accurate repositioning of a traveling work-guide, as for example in the event of thread breakage in spiral stitching operations.

Other and more specific objects of the invention will be apparent from the following description andclaims. I g

The invention comprises the devices, combinations and arrangements of parts hereinafter described in connection with the accompanying drawings, which illustrate a preferred embodiment of the invention and in which:

Fig. 1 is a perspectiveview of a sewinginachine unit supported by a base-unit which contains the improved work-guiding mechanism. Fig. 2 represents a vertical section of the work-guide carrier taken lengthwise of the guide-carrier adjusting spindle. Fig. 3 represents a fragmentary vertical section of the guide-carrier, taken substantially on the line 3-3 of Fig. 2 and showing a portion of a modified lead-screw. Fig. 4 is a top-plan view of the work-guide with the top plate of the workguide removed and showing a portion of the leadscrew. Fig. 5 represents horizontal sections taken at different levels of the right'hand' end portion ofthe base-unit pedestal; the sections being taken in substantially the horizontal planescontaining the axes of rotation of the respective shafts shown. Fig. 6 represents a vertical section of the intermediate shaft driving worm and taken on substantially the line B6 of Fig. 5. Fig. 7 represents a vertical section of the work-guide and its carrier, the section being taken' in substantially the vertical plane containing the rotation-axis of the lead-screw. Fig. 8 represents a verticalsection ofa portion of the base-unit pedestal and of the sewing machine bed-plate, the section being taken in substantially the vertical plane containing the axis of rotation of the intermediate shaft which engages the lead-screw shaft.

The sewing machine unit illustrated in Fig. 1 of the drawings'has a bed-plate [0, from one end of which rises the hollow standard H of a bracket-arm l2 which terminates in a head l3 and overhangs the bed-plate Ill- .While the stitchforming and work-feeding mechanism of the sewing machine shown in theidrawings is struc- Claims. (01. 112-2) 2. turally substantially the same as disclosed in the U. S. Patent of S. ZOhis,'N0. 2,267,581, Dec. 23, 1941;, itwill be understood fromthe following description that other kinds" and varieties of stitchformingand work-feeding mechanisms could be employed'witho'ut departing from the spirit and scope of the'present invention.

As more fully shown and described in said prior Patent No. 2,267,581; the sewing machine illustrated has a; vertically re'ciprocatory needle land a complemental loop-taker I5; said loop-taker being rotated'by suitable connections (not shown) with a bed-shaft 16 disposed at the underside and extending horizontally lengthwise of the bed-plate II). The bed-shaftlfi is "rotatably'journaled in aball bearing I! supported by'the' bed-plate Ill and, adjacent said ball-bearingl'l, a peripherally .grooved pulley i8 is secured bya screw 19 upon the end of the bed-shaft l6 which is disposed below the bracket-arm standard ll. -Engaging the pulley I8 is a clip-belt-ZO by means of which the bed-shaft 1-6 is rotated once for each complete reciprocation of the needle I 4. The work is advanced across the bed-plate It] by a conventional feed-dog 2| which operates through a work-supporting throat-plate 22 and is opposed in its work-engaging movements by a spring-depressed presser-foot 23.

' The sewing machine above generally described is removably supported upon a base-unit having a frame including a hollow pedestal 24 and a trough-shapedarm 25 extending laterally from the upper portion of the base 24 andfree at its outer end. The arm 25 of the base-unit and the sewing machine bed-plate l0 together provide a free work-arm adapted to accommodate endless works" Secured by screws ZBupon the front face of the pedestal 24 is a bracket 21 formed with spaced bearing bosses 28 and 29 having horizontally alined apertures 30 and 3|. Rotatably journaled in, the bearing-apertures30,;3| of the bracket 2'! is a horizontally disposed shaft 32 extendin lengthwise of the base-unitarm- 25 and having one end portion thereof in the region'of the free end of the work-arm freely suspended. The shaft 32 is held against endwise-movement in the bearing-bossesZB and 29 by suitable collars 33. The suspended portion of the shaft 32 is provided with a spiral thread 34' of slow lead to form a leadscrew; the spiralthread 34 extending from the free end of the shaft 32 and preferably terminating'short of the bracket-boss 28. Adjustably secured upon the shaft 32, between the lead-screw thread'thereof and the bracket-boss 28, is a stopcollar 35, of which the function will be hereinafter described.

The end of the lead-screw shaft 32 opposite to the threaded end thereof is provided within the bracket-boss 29 with a worm-gear 36. hi driving engagement with the under side of the wormgear 36 is a worm 37 carried by the forward end of an intermediate shaft 38 disposed horizontally transverse to the shaft 32 and extending into an opening 39 provided in the bracket-boss 29. The intermediate shaft 33 is journaled eccentrically in a bearing-bushing '40 secured by a screw 4! for turning adjustment in an internal bearing-lug 42 of the pedestal 24. This construction not only provides for convenient assembly of the shafts 32 and 38 in the proper intermeshing relation of the worm-gear 36 and worm 31, but also facilitates replacement of the lead-screw-shaft 32.

Secured upon the rearward. end of the intermediate shaft 38, by a screw 43, is a worm-gear 44 engaged by a driving worm 45, disposed above the worm-gear. 44 and rotatably journaled upon a fixed stud 43. of the drawings, the stud 45 is secured bv a screw 4! in a wall of the pedestal 24 to extend inwardly from said wall in substantial axial alinement with the bed-shaft E6 of the sewing machine and in parallel relation to the lead-screw shaft 32. At its inner end, the worm 45 has a driven-member in the form of a flange 48 provided with a crankpin 49.

The bed-shaft pulley it of the sewing machine has an internal hub l3". Secured by a screw 53 upon the pulley-hub I8 is a recessed drivermember in the form of a collar provided with a crank-pin 52 disposed to engage the crank-pin 49 of the worm 45, thereby to rotate said worm 45 with the bed-shaft I6. The described driving arrangement for the worm 45 provides for ready removal of the sewing machine unit from the base-unit and permits of convenient association of a sewing machine unit or different sewing machine units with the base-unit.

Slidably supported upon the threaded free end portion of the lead-screw shaft 32, for travel lengthwise of said shaft and, therefore, crosswise of the line of feed of the sewing machine, is a work-guide carrier 53 having a lead-screw shaft receiving aperture 54, Extending forwardly from one end of the carrier 53 is a boss 55 having an aperture 56 extending transversely of the aperture 54 and connected therewith by a follower-clearance opening 51. Secured inv the carrier-boss 55 by a screw 53, for turning adjustment, is a bearing-bushing 53 formed with a flange 60 in engagement with the front end of thecarrier-boss 55. The bearing-bushing 59 is As illustrated in Figs. 5 and 6 pinion 63 functions as a follower-nut which is complemental to the lead-screw thread 34 in effecting feeding of the carrier 53 lengthwise of the shaft 32 during rotation of said shaft 32. However, the spindle 62 may be readily rotated by manual manipulation of the nut 66 when the shaft is stationary, to attain accurately any desired position of the carrier 53 upon the shaft 32. As the lead-screw end portion of the shaft 32 is free of the supporting base 24, the carrier 55 may be conveniently applied to and removed from the shaft 32 endwise thereof.

Any suitable form of Work-guide may be associated with the carrier 53. The tubular workguide illustrated in Figs. 1, 4 and '7 of the drawings comprises adjacent bottom-plates 5 9 and ill individually secured for adjustment relative to each other upon the carrier 53 by pairs of screws ii and. 72 passing freely through elongated countersunk slots '53 and i4 provided in and extending transversely of the respective plates. The plates 59 and ill have segmentally curved side edges, and the relatively remote curved side edges of the respective plates are bent upwardly and backwardly to form flanges overhanging the plates, thereby to provide spaced and opposed edge-guides l5 and it. Detachably supported by the overhanging side'flanges of the plates 59 and 73, in spaced relation to said plates, is a top plate 'l'l having'its front edge portion bent back upon itself to form a loop 18 entered by the front ends of said flanges. 'The right hand edge portion of the top-plate H is provided at the upper side thereof with a supporting and. locating block it which is recessed to receive the flange of the bottom-plate ill, thereby to support and to locate the right hand edge of the top-plate T! in spaced relation to the edge-guide '15. By this means, increased clearance is provided within the work-guide at the right hand side thereof,

eccentrically provided with a, bearing-aperture Rotatably journaledin the bearing-aperture 6! of the bushing59is a spindle 62 extending horizontall transversely of the shaft 32 and provided .at its rearward end with a cylindrical head 63 held in frictional engagement with the inner end of the bushing 59. The spindle-head 63 comprises a pinion having teeth 54 formed to mesh with the lead-screw thread 34 of the shaft 32. Securedbv a screw 65v upon the forward end of the spindle E2 is a knurled nut 55 having an axial cavity 61. Housed in the nut-cavity 6? is a coil-spring 68 interposed between the nut 66 and the bushing 53 and functioning to restrain the spindle 62 against rotation during stitching operations of the sewing machine. When the spindle 62 is thus restrained against rotation, the

for work having a rib at one edge as in sailors hat brims.

The described Work-guide merely rests upon the bed-plate ill of the sewing machine; the connection between the work guide carrier 53 and the lead-screw shaft 32 permitting pivotal move- 'ment of the carrieri53 uponsaid shaft. This construction therefore provides for readily swinging the work-guide forwardly about the shaft 32 into an out of the waypositi'on.

While'o-bviously capable of other uses, the present improvement is particularly well adapted for spirally s-titching'the brims of sailors hats. "The brim to be stitched ispassedthrough the workguide and is directed by the edge-guide 'Hi'thereof during the feeding of the brim by the feed-dog 22 across the bed-plate Ill. In the operation of the sewing machine, thework is fed past the stitch-forming mechanism, across the bed-plate ill by the feed-dog 21 and is at the same time progressively shifted sidewise to the right by the rotating lead-screw '32.

In its sidewise travel, the work-guide carrier 53 ultimately engages'the stop-collar 35 and is thereby arrested in a location' of the work-guide predetermined by the setting of the stop-collar 35. This is permitted in the int'ermeshing relation of the spindle '33 and'the lead-screw thread 34, by reason of the fact that the positive stopping of the carrier 53 by the collar 35 serves to overcome the rotation-restraining friction. imposed by the spring '58 upon the pinion 63, there by inducing the spindle 62 to rotate idly in the carrier 53. 4 h

In the modified form of construction" illustrated inFig, 3 of thedrawings, a substitute rotary shaft 32' having a spiral lead-screw thread 34' is provided with a circumferential groove 80 at a location in the length of the shaft which corresponds substantially to the position of the left hand end of the stop-collar 35 above described; In this form of construction, the pinion 63 rides off thelead-screw thread 34 in the travel of the WQrk-guidecarrier 53, thereby bringing the carrier to rest. 7,

Having thus set forth the nature of the inven-'- tion, what Iclaim herein is:

1, A spiral stitching mechanism comprising, in

combination, a base-unit including a supporting pedestal'having' a lateral arm free at one end, a lead-screw rotatably supported by said base-unit and extending lengthwise of said arm, a workguide operatively connected to said lead-screw to derive lateral movements therefrom upon rotation of the lead-screw, a sewing machine unit removably Supported upon said base-unit and having a frame including a bed-plate anda bracketarm overhanging the bed-plate, said sewing machine unit containing stitch-forming and workfeeding mechanism including. a rotary drivermember, a driven-member journaled upon said pedestal coaxially of said driver-member and disposed for rotating engagement by said drivermember, and operative connections with said driven-member for rotating said lead-screw 2. A spiral stitching mechanism comprising, in combinatioma baseunit including a supporting pedestal having a lateral arm free at one end, a lead-screw rotatably supported by said base-unit and extending lengthwise of said arm, a workguide operatively connected to said lead-screw to derive lateral movements therefrom upon rotation of the lead-screw, a sewing machine unit removabl supported upon said base-unit and having a frame including, a bed-plate and a bracket-arm overhanging the bed-plate, said sewing machine unit containing stich-forming and work-feeding mechanism including a rotary bed-shaft disposed below said bed-plate and substantially parallel to said lead-screw, a driver-member carried by said bed-shaft and having a crank-pin, a driven-member journaled upon said pedestal coaxially of said bed-shaft and having a crank-pin disposed for engagement by said crank-pin of the driver-member, an intermediate shaft rotatably journaled in said pedestal and extending crosswise of said leadscrew, worm and worm-gear connections between said drivenmember and said intermediate shaft, and worm and worm-gear connections between said intermediate shaft and said lead-screw.

3. IA. spiral stitching mechanism comprising, in combination, a base-unit including a supporting pedestal having a lateral arm free at one end, a lead-screw rotatably supported by said base-unit and extending lengthwise of said arm, a workguide operatively connected to said lead-screw to derive lateral movements therefrom upon rotation of the lead-screw, a sewing machine unit removably supported upon said base-unit and having a frame including a bed-plate and a bracketarm overhanging the bed-plate, said sewing machine unit containing stitch-forming and workfeeding mechanism, a rotary driver-member carried by the sewing machine mechanism, a bearing-bushing extending crosswise of said leadscrew and supported by said pedestal for turning adjustment about its longitudinal axis, an intermediate shaft rotatably journaled eccentrically in said bearmg-bushing, Worm and worm-gear connections between said intermediate shaft and all) said lead-screw, and operative connectionsfor rotating said intermediate shaft from said drivermember. 7

T 4. A spiral stitching mechanism comprising, in combination, a base-unit including a supporting pedestalhaving a lateral arm free at one end, a lead-screw rotatably supported by said baseunit and extending lengthwise of said arm, a

work-guide operatively connected to said leadscrew to derive lateral movements therefrom upon rotation of the lead-screw, a sewing machine unit removably supported upon said base-unit and having a frame including a bed-plate and a bracketearm overhanging th bed-plate, said sewing machine unit containing stitch-forming and work-feeding mechanism including a rotar bedshaft disposed below said bed-plate and substantially parallel to said lead-screw, a driver-member carried by said bed-shaft for rotation therewith, a driven-member journaled upon said pedestal coaxially of said bed-shaft and disposed for rotating engagement by said driver-member, a bearing-bushing extending crosswise of said lead-screw and supported by said pedestal for turning adjustment about its longitudinal axis, an intermediate shaft rotatably journaled eccentrically in said bearing-bushing, and lead-screw rotating gears connecting driven-member, intermediate shaft and lead-screw.

5. A work-guiding base-unit support for sewing machines, comprising, a pedestal having a lateral arm free at one end and adapted to support a sewing machine, a lead-screw shaft rotatably supported by said pedestal and extending lengthwise of said arm, said shaft having a threaded free end portion of its length disposed in the region of the free end of said work-arm, a crank-member supported by said pedestal for rotation about an axis substantially parallel to the axis of rotation of said lead-screw shaft, an intermediate shaft rotatably journaled in said pedestal and having gear connections with said crank-member and said lead-screw shaft, a work-guide carrier supported to travel lengthwise of said lead-screw shaft, and a follower-nut supported by said carrier and disposed in carrier-propelling engagement with the thread of said lead-screw shaft.

6. In a work-guiding device for sewing machines, a rotary shaft restrained against endwise I movement and provided with a lead-screw thread, a work-guide carrier adapted to be propelled endwise of said shaft, a pinion rotatably journaled in said carrier and disposed in mesh with the leadscrew thread of said shaft, and means for restraining said pinion against rotation, thereby to convert said pinion into a follower-nut.

7. In a work-guiding device for sewing machines, a rotary shaft restrained against endwise movement and provided with a lead-screw thread, a work-guide carrier adapted to be propelled end.. wise of said shaft, a pinion rotatably journaled in said carrier and disposed in mesh with th leadscrew thread of said shaft, and friction means for restraining said pinion against rotation, thereby to convert said pinion into a follower-nut.

8. In a work-guiding device for sewing machines, a rotary shaft restrained against endwise movement and provided with a lead-screw thread, a Work-guide carrier adapted to be propelled endwise of said shaft, a spindle rotatably journaled in said carrier and extending cross-wise of said shaft, said spindle having a peripherally toothed head in mesh with the lead-screw thread of said shaft, and means for restraining said spindle againstrotation, thereby to convert v aid head into a follower-nut.

9. In a work-guiding device for sewing niachines, a rotary shaft restrained against endwise movementand provided with a lead-screw thread, a work-guide carrier adapted to be propelled endwise of said shaft, a bushing journaled in said carrier for turning adjustment about an axis transverse to the rotation-axis of said shaft, a spindle rotatably journaled eccentrically in said bushing and carrying a pinion in mesh with the lead-screw thread of said shaft, and means for restraining said spindle against rotation, thereby to convert said pinion into a follower-nut.

10. In a work-guiding device, for sewing ma chines, a rotary shaft restrained against endwise movement and provided with'a lead-screw thread, a work-guide carrier adaptedto be propelled endwise of said shaft, a pinion in mesh with the leadscrew' thread of said shaft and journaled in said carrier for rotation about an axis transverse to the rotation axis of said shaft, means providing for adjustment of said pinion toward and from said shaft, and means for restraining said pinion against rotation, thereby to convert said pinion intoafollower-nut. r i

11. In a work-guiding device for sewing machines, a rotary shaft restrained against endwise movement and provided with alead-screw thread, a work-guide carrier adapted tobe propelled endwise of said shaft, a spindle journaled in said carrier for rotation about an axis transverse to the rotation-axis of said shaft, a pinion carried by said spindle and disposed in mesh with the lead-screw-thread of said shaft, a manually rotatable nut carried by said spindle for rotating said pinion, and spring means for frictionally securing saidspindle against rotation in said carrier, thereby to convert saidpinion into a follower-nut.

12. In awork-guiding device for sewing .machines, a rotary shaft restrained against endwise movement and provided with a lead-screw thread, a transversely apertured work-guide carrier, a

lead-screw shaft extending through one of the apertures of and 'slidably supporting saidcarrier, a spindle rotatably journaled in the other aperture of said carrier, a pinion carried by one end of said spindle and disposed in mesh with the thread of said lead-screw, means carried by the other end of said spindle and disposed externally of said carrier for manually rotating said pinion, and means for securing said spindle against rotation, thereby to convert said pinion into a follower-nut.

13. In a work-guiding device for sewing machines, a rotary shaft restrained against endwise movement and providedwith a lead-screw thread, a work-guide carrier adapted to be propelled endwise of, said shaft, a pinion rotatably journaled in said carrier and disposed in mesh with the lead-screw thread of said shaft, manually operabie means for rotating said pinion, and means for securing said pinion against rotation, thereby to convert said pinion into a follower-nut.

14. In a work-guiding device for sewing machines, a rotary shaft restrained against endwise movement and provided with a lead-screw thread, a work-guide carrier adapted to be propelled endwise of said shaft, a pinion rotatably journaled in said carrier and disposed in mesh with the lead-screw thread of said shaft, yieldable means for secur ng said pinion against rotation, and means limiting the travel of said carrier in one direction.

25. In a work-guiding device for sewing machines, a rotary shaftrestrained against endwise movement and provided with a lead-screw thread, a work-guide carrier adapted to be propelled endwise of said shaft, a pinion rotatably journaled in said carrier and disposed in mesh with the lead-screwthread of said shaft, yieldable means for securing said pinion against rotation, and a stop-member carried by said shaft and disposed in the path of movement in one direction of said carrier.

, a Y WALTER MYERS. 

